Main Engine 4-Stroke · Main Engines (4-Stroke)
The Wärtsilä 9LW25 is a medium-speed trunk piston engine designed for maritime applications. Manufactured by Wärtsilä, this model operates with a power output of 2475 kW and features nine cylinders in an L configuration. The engine uses heavy fuel oil (HFO) or marine gas oil (MGO) as its primary fuel type, though it can also operate on dual-fuel modes using liquefied natural gas (LNG) or ammonia (NH3). With a bore of 250 mm and a stroke of 350 mm, the engine runs at 1000 rpm. It is certified for native Tier III emissions in LNG mode and can be equipped with Wärtsilä NOx Reducer (NOR) to meet these standards when using diesel or ammonia as fuel. Regular maintenance checks include inspecting high-pressure Common-Rail pump wear, monitoring the crankcase ventilation system, and checking lube oil analysis for signs of wear in continuous low-load operation.
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